In alphabetical order, the eight founding core members of The Rails Foundation are: Cookpad, Doximity, Fleetio, GitHub, Intercom, Procore, Shopify, and 37signals. These corporate members have together generously endowed the foundation with $1,000,000 USD in seed funding to make a real difference on all the aforementioned areas of improvement.

Source: Ruby on Rails - The Rails Foundation kicks off with one million dollars

Very happy to see Doximity on this list!